Finder-starting system.



A. E. -LUNDELL.

FINDER STARTING SYSTEM.

APPLICATION FILED SEPT. 11. 1916.

Patented Jan. 21, 1919.

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I UNITED STATES PATENT OFFICE.

ALBEN- ELUNDELL, or NEW YORK, N. Y., ASSIGNOR To wEsTEENEnncirniceoinrANr, INCORPORATED, on. NEW YORK, N. Y; A CORPORATION onNEW YORK.

EINnEnfls'r nTING SYSTEM. 1

' Spee ification of Letters Patent.

Patented Jan; 21, 19in.

a nea filed September 11, 191a; seriai N8. 119,479.

To all whom it may concern:

, Be it known that I, ALBEN E. LtiNneLL, a citizen of the United States,residing at New York, in the county of Bronx and State of Nework, haveinvented certain new and useful Improvements Finder-Starting Systems, ofwhich-the" following is a full, clear, concise, and exact description;

' This inyention relates to telephone cit change system's employingmachine switch ing, and more particularly to systems of the type inwhich line finder switches are deed. The' object- "of the presentinvention is. to

reduce to a minimum the timeinterval required between the startingoffinders in search o'fl'calliing lines in the same group.

The invention has been-shown applied to a s'e'mi automatic system of thewell-known power driven type employing switches of the panel type, butmay obviously be arranged foruse ina variety-of systems.

Heretofore' in Panel Systems employing line finders, it has been thepractice to permit only onefinder to start seeking a calling line at atime.- Although means have been provided for responding immediately to asecond'call if in 'a'gr'ou other than that of the first calling line,means have been provided'for delaying the response to a second call inthe same group,'in some systems'until the first callingline'has beenreached, and in other systems until a time measuring switch has beenfully operated in order to measure an interval slightly greater than thetime required for the brush set to travel to the lastline of a group.

A feature of the present invention is the provision of means forstarting a second line finder when a second call from the same group isoriginated, suchmeans being ineffective if only one call at a time comesin from that group. The first finder will seize the calling line thecontacts of which are first reached, while the secondfi'nder will seizethe other line. The system shown func 'In the drawingthe lines of twocalling subscribers in the same group are represented. The apparatusdiagrammatically indicated in the dotted rectangle at B' common to thegro ip which includes such subscribers. H The dotted rectangle atBindicates similar apparatus common to a second group of subscribers, Fand E show schematically t'w'o' line finders and circuits therefor; At Ais shown an allotterfor sue; cessively bringing the finder switches intoposition tobe started. a

The finder switches used are preferabl of the type disclosedanddescribed in Patent No. 1,177,044. The controlling sequence switch andthe allot'te'r switch are preferably of a mechanical structure similarto that disclosed in Patent 1,127,808. I

The operation of the system when only one call is originated will firstbe described. When the subscriber at substation 1 dc} sires to initiateacall h'c removes'his receiver from its hook, whereupon a, line relay 2'is energized over t'he'line conductors and arma; tures and back contactsof a cutoff relay 3 in the well-known manner. At its righthand armatureand front contact, relay 2 places a ground through a resistance 4 on themultiple test terminals 5 in which the for relay? from grounded battery,winding of relay 7, inner right-hand armature and front contact of relay6, and winding of relay 6 to ground over the path previously described.Trip magnet 13', common to the group B," is energized in parallel, fromgrounded battery, Winding of magnet 18,

outer righth'a'n'd armature and front contact of relay 6 to ground, as'described. The operation of magnet13 moves a trip rod to release a setofbrushes serving the desired group on whichever finder starts in searchof the calling line,- i

The operation of relay 7 at its right-hand armature holds open starterwire 8 and prevents the operation of relays 6 of any other groups untilthe finder started by the first call has reached the desired stage ofoperation.

At its left-hand armature relay 7 completes a starting circuit for thefinder indicated at F. This circuit extends from grounded battery, powermagnet 100 of the finder sequence switch, sequence switch con tact 101,conductors 102, 108, to ground at the left-hand armature and frontcontact of relay 7. Sequence switch 100 moves from its first to itssecond position under the control of normal spring 104.

It is to'be understood that the sequence in which the finder switchesare started is controlled by an allotter indicated at A, and that onlyone finder switch at a time is resting in position 1. After the finderswitch F moves out of position 1 and the brush 120 has moved intoengagement with commutator segment 12% by means of circuits to bedescribed, a circuit is completed from grounded battery, power magnet123 of an allotter switch A, contact125 controlled by allotter A,commutator segment 12 1, and brush 120 to ground. The allotter A is thenmoved from its first to its second position. On arriving in its secondposition, a circuit is completed for the sequence switch of finder Ffrom grounded battery, power magnet 200 of the sequence switch of finderF, contact 201, conductors 202, 203, and contact 126 to ground. Thesequence switch at F is moved from its eighteenth to its first position,andthe finder F is now in a position to be started when the common relay7 is again energized by the initiation of a call in any of the groups.The finder sequ nce switches rest in the eighteenth position upon thecompletion of the conversation, as will be described, and await the action of the allotter.

To return now to the operation of the finder F, it will be rememberedthat the se-' quence switch of this finder is now in the secondposition. Atthis time a circuit is closed for up-drive magnet 105 fromgrounded battery, winding of magnet 105, armature and back contact ofrelay 106 to grounded battery at sequence switch contact 107. When thefinder test brush 108 engages test terminal 5 of a line calling, a

circuit will be completed from grounded bat-' tery, winding of relav106, sequence switch contact 109, brush 108, terminal 5, righthandarmature and front contact of relay 2 to ground through resistance 1.The operation of relay 106 opens the circuit of the up-drive magnet 105and completes a circuit for moving sequence switch 100 out of its secondand into its sixteenth position, this circuit being from groundedcontact 107, armature and front contact of relay 106, winding of powermagnet 100 of the finder sequence switch to grounded battery.

in positions 3 to 16 of the sequence switch, battery is supplied toterminal 5 from grounded battery, resistance 110, sequence switchcontact 111 and brush 108. Marginal'cutolf relay 8 operates when theresistance of relay 106 is removed from the circuitQ Cutoff relay 3removes the control of the line relay 2 from the calling subscriber inthe well-known manner.

During the upward motion of the brush shaft, brushes 120 and 127 arecarried up ward over commutator segments 121, 124 and 128, respectively.When brush 127 engages segment 128 a circuit is completed fromgroundedbattery, left-hand armature and front contact of relay 6,right-hand winding of relay 11, conductors 1 1 and 15, sequence switchcontact 129, segment 128, brush 127, to ground. Relay 11 is energizedand opens the circuit of relay 6; relayv 7 and trip magnet-13 beingdeenergized at the same time. Relay 11 at its trontcontact and armaturecompletes a locking circuit for itself from grounded battery, left-handwinding of relay 11, armature and back contact of a-marginal'relay 16,armature and" front contact of relay 11, left-hand armature and frontcontact of relay 2 and resistance 12 to ground. When the cut-ofl relay 3is energized, line relay '2 is denen gized and the locking circuit forrelay 11 is broken. The apparatus is now in condition to start anotherfinder;

-When the finder F arrives in position 16 a calling subscriber mayconverse with an operator whose position is indicated at 0', who, uponascertaining the numberof the desired line, may set up a connection tothe wanted subscriber inany desired manner,

a train of automatic switches being indicated in the present instance at112 and 113.

At the conclusion of the conversation, the operator at O is informed inthe well-known manner by the lighting of supervisory signals controlledby relays 11 1, 115. She then depresses a key 116, completing a circuitfrom ground, contact of key 116, sequence switch contact 117, thewinding of power magnet of sequence switch 100, to grounded battery. Thesequence switch then moves into the seventeenth position, at which timea circuit is completed for downdrive magnet 118 from grounded battery,winding ofmagnet 118, sequence switch contact 119 to ground. The brushset is then returned to normal position, and when the commutator brush120 engages segment 121 a circuit is completed from ground. brush 120.segment 121, sequence switch contact 122, winding of the power magnet ofsequence switch 100 to V grounded ba e y-- T e sequence "switch thenmoves from p sition 7 into re it n .8. Whe it r m in a i g the. at ics tallotterA- I the ca l i or g na ed n group B before bru h 1210 finder Fas. reached se rmen l eX-6-Qf s h roup ann t ersiz due to the energized:cond tion, of 09maien. r lay s een, how ver, relay 7 s de rg zed, a circi will be o p e ed 0 relay (i -from grounded, battery, right-hand armaure and back conta t Qf e y ductors 8 and 17, to relay 6, and ground atthe lefthand armature of the line relay of the liner calling aspreviously described. The operation of relay 6 allows relay 7 to beenergized over a path from g ound d hat: tery, winding of relay 7, innerright-hand armature and back contact of the relay 6 of group B,conductor 18, to ground as described in the operation of the calloriginated in group B. Relay 7, upon energiza tion, will complete astarting circuit for finder F from ground, left-hand armature and frontcontact of relay 7, common conductor 103, conductor 204, contact 205,winding of power magnet 200 of the sequence switch associated withfinder F, this sequence switch having been moved into normal positionafter the operation of finder F has reached a certain stage ofoperation, as previously described, by the action of allotter A. It isto be understood that the starter wires 8 and 18 are extended throughall the groups served by the finders.

The operation of the system, in case two calls are originated in group Bin close succession, will now be discussed. The first call will operatethe group apparatus as previously described. When, however, relay 11 isenergized, if a second call is in existence, there will be two paths toground through resistances 12 in multiple. The decreased resistance ofthe path to ground allows marginal relay 16 to operate, opening at itsarmature and front contact the locking circuit of relay 11. This relaywill then immediately deenergize and allow relay 6 to be energized inresponse to the second call in the group, regardless of the position ofthe finder searching for the first line. The operation of relays 6 and 7serves to start an allotted finder in the previously described manner.It will thus be seen that in case of two calls from the same group whichmay be simultaneous or in close succession, a finder will be started andas soon as brush 127 engages segment 128. circuits are completed bywhich a second finder will be started in search of the second line.

It would be possible that this first finder would seize the terminals ofthe second line if they are lower in the panel, but this would not beharmful since the second finder would ,etieue unt it ound he. erm sh Wlte ai e s 1. In a tale hone exchange system, a plurality of calllnsubstation lines arranged in groups, a p uralityof finder switchesserving said lines, means to start a finder te- Select a desir d' eu ato e v for a calling line "in said esired group upon the. initiation ofa call, means to, move a sce d finder to. a posit to. b rt and meanstostart said second finder in ea h. of. a san ca l in i he s gr en as seeSa eco fi der has. me e t me a. maiden t b st rt d 2. In a telephoneexchange system, a plurality of calling substation lines arranged ingroups, a plurality of finder switches serving said lines, one only ofsaid switches being in a position to be started, means to start saidpositioned finder in search of a calling line, means to move a secondfinder into a position to be started as soon as said positioned finderhas begun to search for a calling line, and means to start said secondfinder in search of a second calling line in the same group.

3. In a telephone exchange system, a plurality of calling substationlines arranged in groups, a plurality of finder switches serving saidlines, an allotting switch for successively moving said finder switchesinto a position to be started as soon as an allotted finder starts itsoperation. means to start an allotted finder in search of a callingline, and means to start a second finder in search of a second line inthe same group as soon as said second finder has been allotted.

4. In a telephone exchange system, a plurality of calling substationlines arranged in groups, a plurality of finder switches serving saidlines, sequence switches associated with said finder switches, anallotting device for moving said sequence switches successively intoposition to start their respective finders, means to start a finder insearch of a calling line, means including said allot'ter and actuatedupon the starting of the operation of said first finder for moving thesequence switch of a second finder into a position wherein said secondfinder may be started, and means to start said second finder in searchof a second calling line in the same group as soon as the sequenceswitch of said second finder has been moved to starting position.

5. In a telephone exchange system, a plurality of calling substationlines arranged in groups, a plurality of finder switches serving saidlines, an allotting switch for successively moving said finder switchesinto a position to be started, a relay individual to said groups oflines, said relay controlling the starting of allotted finders, a secondrelay, a circuit for said first relay extending through back contacts ofsaid second relay, means for energizing said second relay as soon as anallotted finder has started, a locking circuit for said sec- 0nd relay,and means for holding open said locking circuit if another call ispresent in the same group.

6. In a telephone exchange system, a plurality of calling substationlines arranged in groups, a plurality of finder switches serving saidlines, an allotting switch for successively moving said finder switchesinto a position to be started, a group relay newness controlling thestarting of an allotted finder, a second relay, means for energizingsaid second relay when a finder has been started, a circuit for saidfirst relay extending through back contacts of said second relay, amarginal relay, a locking circuit for said second relay extendingthrough *backcon- ALBEN E. LUNnn n Copies of this patent may be obtainedfor five cents each, by addressing the Commissioner oflat'ents,

Washington, D. C.

